RCW 69.40.020

Any person who shall sell, offer to sell, or have in his or her possession for the purpose of sale, either as owner, proprietor, or assistant, or in any manner whatsoever, whether for hire or otherwise, any milk or any food products, containing the chemical ingredient commonly known as formaldehyde, or in which any formaldehyde or other poisonous substance has been mixed, for the purpose of preservation or otherwise, is guilty of a class C felony, and upon conviction thereof shall be imprisoned in the penitentiary for the period of not less than one year nor more than three years.